Npn-silicon planar transistors - with small initial potential and base current values

摘要

In the prodn of npn-Si planar transistor, with 2 stage-emitter diffusion, the semiconductor, after emitter diffusion, is tempered in mixed gas (12.5% H2, 87.5% N2) or moist N2 before applying the emitter contacts at 900 degrees C and after applying the contacts at 400 degrees C. After the first diffusion in an atmos contg. the defect material for the emitter diffusion, the semiconductor surface is given a pyrolytic dielectric coating, then further diffusion of the defect material takes place in an inert gas atmos, whilst tempering in a N2 atoms is carried out before applying the emitter contacts. Tempering at 900 degrees C and then at 400 degrees C causes 'trap removal' but the real part of the initial potential goe and the base current IB of the transistors are inversely proportional. Using the modified process, it is possible to produce transistors with both small IB and small goe values.